Removing anodized coating

I was going to use ZOOP SEAL or get them powdercoated in clear once they are polished.

That's good!
If your aluminum is thin then be extra careful about using chemical strippers. Any chemical that will remove the anodized layer will also remove or etch the exposed aluminum.

If you decide to use an abrasive material to remove the anodized layer then use a continuity tester to check the aluminum surface. The anodized layer does not conduct electricity whereas bare aluminum will.